Process of making abrasive wheels.



CLENClE ROSGO COM]? WY, A CORPORATION OT MASSACHUSETTS.

PROCESS O]? MAKING ABRASIVE WHEELS.

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, No Drawing.

To all whom it may concern Be it known that l. (iLAllHlNCE -lloscor: Time, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Process of Making Abrasive Wheels, of which the following is a specification.

This invention relates to a process of making abrasive wheels and more specifically to a' process of making abrasive wheelsin which a supplemental bond is embodied.

The details of my improved process are fully described in the following specification and the novel features thereof are specifically defined in the appended claim.

My improved process is more particularly applicable to abrasive wheels having a porous unitary structure. Such wheel maybe generally defined as having the abrasive material unitedand held together by someform of silicate binder and are classified commercially as vitrified wheels and silicate wheels. Tn thefirst class, the silicate binder is in the form of clay mixed with. other mineral silicates which are partially fused by burning in a kiln, and form a porous mass more or less resembling porcelain or glass, in which the abrasive particles are firmly embedded. Tn the so-called silicate wheels, the principal binding constituent is silicate of soda, commonly known as water glass. This silicate, together with certain mineral-powders, is mixedwith the loose grains of abrasive material. After being molded to the desired shape and size, the wheel thus termed is dried and is then heated to a suiticient temperature to cause the silicate of soda to react with the other minerals to term a hard, porous mass which securely holds the abrasive grains in place. Each ot these two types of wheels is distinguished by the use oil .a' silicate binder and by the fact that the wheelthus termed possesses a porous, unitary structure. The silicate binder in either type may be considered as a thin envelop inclosing and fining the abrasive grains in position.

en the wheel is in use the grains upon the periphery thereof are subject to the abrasive action between the wheel and the work and "alga to severe torsional and impact strain-sf The silicate binder, when formed into a-porons. mass having the abrasive grains distributed therethrough, pos- Speeification of Letters Patent.

'very slight degree of toughness.

sesses substantially no resilience and only a qualities of resilience and toughness are most essential for resisting the torsional and imat any temperature which will be attained in grinding operations. I have found that these-called synthetic resins are particularly adapted for this purpose. These resins are -manutaetured under various trade names such as hakelite, condensite, amberoid, plastic, tenoform, and the like, and they have in common the quality of receiving a permanent set when heated to a moderate temperature. 7

ln practising my improved process, ll form an abrasive wheel having a porous unitary structure in the usual manner, and fill the voids of the structure with one of these synthetic resins insolution or in liquid form. The wheel is then heated to a temperature sutficient to give the permanent set to the supplementary bonding material and is then ready for use.

have found by actual test that wheels thus treated will remove more material per unit of wheel wear and that. they act as they Patented li ers... l2, llllllltl.

Application filed May 28, 1914. Serial No. 841,6?8.

As the,

All

would have done if they were originallymade several grades harder. They also wear trom two to four times longer than similar of the grinding wheels, that they can thereafter be given a permanent set, and that having once received this permanent set they cannot again be liquefied at ordinary grinding temperatures. Such materials can be broadly distinguished from the mineral silicates by the term organic.

Although I have described my invention a porousstructure, dipping said wheel in an unheated solution of synthetic resin, and

therafter heating said wheel and thereby transforming said rsin into a hard tough supplemental bonding material incapable of 15 subsequent liquidation by heat.-

In testimony whereof Ihave hereunto set my hand, in the presence of two subscribing witnesses.

CLARENCE RosooE KING.

Witnesses:

CHAs. T. HAWLEY, C. FORREST WESSON. 

